At what point does a buy a hold investor re-evaluate and which calculation holds more weight for you?

Now as we enter our third year with the house, we are looking at two prospective properties to become our second {International} student house as we are consistently over-subscribed at the existing house.The potential pitfalls with renting a large (10-bedroom) house by the room:1) Zoning may not allow for a rooming house;2) No-one looks after the common areas - we started out with the tenants cleaning the common areas which worked fine the first year (we had the right mix of tenants) but did not work well this year ... ironically, the biggest problems were the two Canadian students in the house who did not pull their own weight.  

They tend to sink down under the weight and it just leads to more foundation issues.

Perhaps the lender is giving primary weight to the sales comparison approach?

The Test Prep course is worth its weight in gold.

Comps are weighted differently for commercial than for sfr.If I buy a duplex or triplex and increase the rent (without making any other changes), will that have a positive effect on the appraised value?

I also would like to run some deal points by some more experienced members to see if terms such as "deal finders fee" etc. are being given proper weight.

I do not put any weight in that equation. 

I never heard the term turn key  in relation to Real estate investing untill about three days ago here on bigger pockets  I've actually been toying with the idea of doing turnkey for people seeing as how I started managing my own properties many years ago and have done so in New York State North Carolina and Florida  I'm still easily able to find deals that are Easley double-digit returns in upstate New York in Central Florida  I'm still a little bit in disbelief that I'm actually able to find deals this good  i'm still a little bit in disbelief that I'm actually able to find deals this good and so many others seem not to be something else innocent it just doesn't seem right to me for some reason I've never even gotten a mortgage on the house the one I lived in many years ago      I guess I've been very fortunate to be able to pay cash for everything Perhaps that  why my returns are so high I basically find the property fix it up and then sell it owner finance holding the mortgage or rent them for the incomePerhaps it's like the guy who lifts weights in his house and after 20 years he goes to the gym and he starts punching 500 pounds and everybody around them is in the shop in disbelief they ask him how he did it and he says well I just never thought that I couldn't do it

Your slab is subject to bending stress from self-weight, dead load, and live load and the tensile stress is resisted by the rebar.